xor: make 'xor_blocks' a library routine for use with async_tx

The async_tx api tries to use a dma engine for an operation, but will fall
back to an optimized software routine otherwise.  Xor support is
implemented using the raid5 xor routines.  For organizational purposes this
routine is moved to a common area.

The following fixes are also made:
* rename xor_block => xor_blocks, suggested by Adrian Bunk
* ensure that xor.o initializes before md.o in the built-in case
* checkpatch.pl fixes
* mark calibrate_xor_blocks __init, Adrian Bunk

Cc: Adrian Bunk <bunk@stusta.de>
Cc: NeilBrown <neilb@suse.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/crypto/Kconfig b/crypto/Kconfig
index 4ca0ab3448d9f3887cd3c64594f0006c71194dfd..b749a1a46e227f923cb2dee9df0939e194954fe0 100644 (file)
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -1,3 +1,9 @@
+#
+# Generic algorithms support
+#
+config XOR_BLOCKS
+       tristate
+
 #
 # Cryptographic API Configuration
 #

diff --git a/crypto/Makefile b/crypto/Makefile
index cce46a1c9dc7ccfea486e92b04a0dd6fec71a28e..68e934b4bee2ddc0ffb4e860a16c129fb79aec1c 100644 (file)
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -50,3 +50,9 @@ obj-$(CONFIG_CRYPTO_MICHAEL_MIC) += michael_mic.o
 obj-$(CONFIG_CRYPTO_CRC32C) += crc32c.o
 
 obj-$(CONFIG_CRYPTO_TEST) += tcrypt.o
+
+#
+# generic algorithms and the async_tx api
+#
+obj-$(CONFIG_XOR_BLOCKS) += xor.o
+

diff --git a/drivers/md/xor.c b/crypto/xor.c
similarity index 81%
rename from drivers/md/xor.c
rename to crypto/xor.c
index 324897c4be4ed04cac7404f008cf17ca0c0f5dbc..8281ac5e68a80dcf777e174db2ecc259e298e184 100644 (file)
--- a/drivers/md/xor.c
+++ b/crypto/xor.c
@@ -26,7 +26,7 @@
 static struct xor_block_template *active_template;
 
 void
-xor_block(unsigned int count, unsigned int bytes, void **ptr)
+xor_blocks(unsigned int count, unsigned int bytes, void **ptr)
 {
        unsigned long *p0, *p1, *p2, *p3, *p4;
 
@@ -52,6 +52,7 @@ xor_block(unsigned int count, unsigned int bytes, void **ptr)
        p4 = (unsigned long *) ptr[4];
        active_template->do_5(bytes, p0, p1, p2, p3, p4);
 }
+EXPORT_SYMBOL(xor_blocks);
 
 /* Set of all registered templates.  */
 static struct xor_block_template *template_list;
@@ -78,7 +79,7 @@ do_xor_speed(struct xor_block_template *tmpl, void *b1, void *b2)
                now = jiffies;
                count = 0;
                while (jiffies == now) {
-                       mb();
+                       mb(); /* prevent loop optimzation */
                        tmpl->do_2(BENCH_SIZE, b1, b2);
                        mb();
                        count++;
@@ -91,26 +92,26 @@ do_xor_speed(struct xor_block_template *tmpl, void *b1, void *b2)
        speed = max * (HZ * BENCH_SIZE / 1024);
        tmpl->speed = speed;
 
-       printk("   %-10s: %5d.%03d MB/sec\n", tmpl->name,
+       printk(KERN_INFO "   %-10s: %5d.%03d MB/sec\n", tmpl->name,
               speed / 1000, speed % 1000);
 }
 
-static int
-calibrate_xor_block(void)
+static int __init
+calibrate_xor_blocks(void)
 {
        void *b1, *b2;
        struct xor_block_template *f, *fastest;
 
        b1 = (void *) __get_free_pages(GFP_KERNEL, 2);
-       if (! b1) {
-               printk("raid5: Yikes!  No memory available.\n");
+       if (!b1) {
+               printk(KERN_WARNING "xor: Yikes!  No memory available.\n");
                return -ENOMEM;
        }
        b2 = b1 + 2*PAGE_SIZE + BENCH_SIZE;
 
        /*
-        * If this arch/cpu has a short-circuited selection, don't loop through all
-        * the possible functions, just test the best one
+        * If this arch/cpu has a short-circuited selection, don't loop through
+        * all the possible functions, just test the best one
         */
 
        fastest = NULL;
@@ -122,11 +123,12 @@ calibrate_xor_block(void)
 #define xor_speed(templ)       do_xor_speed((templ), b1, b2)
 
        if (fastest) {
-               printk(KERN_INFO "raid5: automatically using best checksumming function: %s\n",
+               printk(KERN_INFO "xor: automatically using best "
+                       "checksumming function: %s\n",
                        fastest->name);
                xor_speed(fastest);
        } else {
-               printk(KERN_INFO "raid5: measuring checksumming speed\n");
+               printk(KERN_INFO "xor: measuring checksumming speed\n");
                XOR_TRY_TEMPLATES;
                fastest = template_list;
                for (f = fastest; f; f = f->next)
@@ -134,7 +136,7 @@ calibrate_xor_block(void)
                                fastest = f;
        }
 
-       printk("raid5: using function: %s (%d.%03d MB/sec)\n",
+       printk(KERN_INFO "xor: using function: %s (%d.%03d MB/sec)\n",
               fastest->name, fastest->speed / 1000, fastest->speed % 1000);
 
 #undef xor_speed
@@ -147,8 +149,8 @@ calibrate_xor_block(void)
 
 static __exit void xor_exit(void) { }
 
-EXPORT_SYMBOL(xor_block);
 MODULE_LICENSE("GPL");
 
-module_init(calibrate_xor_block);
+/* when built-in xor.o must initialize before drivers/md/md.o */
+core_initcall(calibrate_xor_blocks);
 module_exit(xor_exit);

diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig
index 7df934d69134436cc2e1f5affb7f681dc0ab1671..24d93d02a1f342f213f7f515fa4f0b3b3415a205 100644 (file)
--- a/drivers/md/Kconfig
+++ b/drivers/md/Kconfig
@@ -109,6 +109,7 @@ config MD_RAID10
 config MD_RAID456
        tristate "RAID-4/RAID-5/RAID-6 mode"
        depends on BLK_DEV_MD
+       select XOR_BLOCKS
        ---help---
          A RAID-5 set of N drives with a capacity of C MB per drive provides
          the capacity of C * (N - 1) MB, and protects against a failure

diff --git a/drivers/md/Makefile b/drivers/md/Makefile
index 38754084eac741462bc677f8c6911b662c719623..71eb45f74171a5c2ac1011917e1e680c63f6bcb3 100644 (file)
--- a/drivers/md/Makefile
+++ b/drivers/md/Makefile
@@ -17,7 +17,7 @@ raid456-objs  := raid5.o raid6algos.o raid6recov.o raid6tables.o \
 hostprogs-y    := mktables
 
 # Note: link order is important.  All raid personalities
-# and xor.o must come before md.o, as they each initialise 
+# and must come before md.o, as they each initialise 
 # themselves, and md.o may use the personalities when it 
 # auto-initialised.
 
@@ -25,7 +25,7 @@ obj-$(CONFIG_MD_LINEAR)               += linear.o
 obj-$(CONFIG_MD_RAID0)         += raid0.o
 obj-$(CONFIG_MD_RAID1)         += raid1.o
 obj-$(CONFIG_MD_RAID10)                += raid10.o
-obj-$(CONFIG_MD_RAID456)       += raid456.o xor.o
+obj-$(CONFIG_MD_RAID456)       += raid456.o
 obj-$(CONFIG_MD_MULTIPATH)     += multipath.o
 obj-$(CONFIG_MD_FAULTY)                += faulty.o
 obj-$(CONFIG_BLK_DEV_MD)       += md-mod.o

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 1c54f3c1cca74fca038b5b4452c9a0504e481e57..33beaa7da085cb487ed3ab47710dec048488df6b 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -5814,7 +5814,7 @@ static __exit void md_exit(void)
        }
 }
 
-module_init(md_init)
+subsys_initcall(md_init);
 module_exit(md_exit)
 
 static int get_ro(char *buffer, struct kernel_param *kp)

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 061375ee6592517cf1796c2ff730b5cefcbc7269..5adbe0b2268421f2aa26036c33535b4020b0865b 100644 (file)
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -918,7 +918,7 @@ static void copy_data(int frombio, struct bio *bio,
 
 #define check_xor()    do {                                            \
                           if (count == MAX_XOR_BLOCKS) {               \
-                               xor_block(count, STRIPE_SIZE, ptr);     \
+                               xor_blocks(count, STRIPE_SIZE, ptr);    \
                                count = 1;                              \
                           }                                            \
                        } while(0)
@@ -949,7 +949,7 @@ static void compute_block(struct stripe_head *sh, int dd_idx)
                check_xor();
        }
        if (count != 1)
-               xor_block(count, STRIPE_SIZE, ptr);
+               xor_blocks(count, STRIPE_SIZE, ptr);
        set_bit(R5_UPTODATE, &sh->dev[dd_idx].flags);
 }
 
@@ -1004,7 +1004,7 @@ static void compute_parity5(struct stripe_head *sh, int method)
                break;
        }
        if (count>1) {
-               xor_block(count, STRIPE_SIZE, ptr);
+               xor_blocks(count, STRIPE_SIZE, ptr);
                count = 1;
        }
        
@@ -1038,7 +1038,7 @@ static void compute_parity5(struct stripe_head *sh, int method)
                        }
        }
        if (count != 1)
-               xor_block(count, STRIPE_SIZE, ptr);
+               xor_blocks(count, STRIPE_SIZE, ptr);
        
        if (method != CHECK_PARITY) {
                set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags);
@@ -1160,7 +1160,7 @@ static void compute_block_1(struct stripe_head *sh, int dd_idx, int nozero)
                        check_xor();
                }
                if (count != 1)
-                       xor_block(count, STRIPE_SIZE, ptr);
+                       xor_blocks(count, STRIPE_SIZE, ptr);
                if (!nozero) set_bit(R5_UPTODATE, &sh->dev[dd_idx].flags);
                else clear_bit(R5_UPTODATE, &sh->dev[dd_idx].flags);
        }

diff --git a/include/linux/raid/xor.h b/include/linux/raid/xor.h
index f0d67cbdea40bcc7428036235ee8ce6e8ab79059..7d6c20b654faa9e435fa592a0de8994008d86228 100644 (file)
--- a/include/linux/raid/xor.h
+++ b/include/linux/raid/xor.h
@@ -5,7 +5,7 @@
 
 #define MAX_XOR_BLOCKS 5
 
-extern void xor_block(unsigned int count, unsigned int bytes, void **ptr);
+extern void xor_blocks(unsigned int count, unsigned int bytes, void **ptr);
 
 struct xor_block_template {
         struct xor_block_template *next;